Axiomatic in the field of physical therapy is that early implementation of a rehabilitation program, comprised of motion and strengthening exercises, is essential to realizing optimal results for regaining functional recovery following surgery or injury to the knee joint.
For patients who have undergone surgery for knee replacement or repair, medical care professionals will routinely recommend protocols designed to enable the patient to control and manage pain and swelling, increase range of motion, and endure progressive weight-bearing, in accordance with the patient's strength level, healing progress, and pain tolerance. Many traditional knee rehabilitation exercises involve hands-on manipulation by a physical therapist, as well as exercises performed by the patient without the assistance of mechanical devices or other individuals.
The object of the present device is, generally, to provide an apparatus to facilitate the attainment of rehabilitation goals for patients or users recovering from knee repair or replacement surgery, by providing an easily portable knee exercise device with which the patient or user, while lying comfortably on a floor or other flat, horizontal surface, can position and maintain his or her leg in an approximately vertical position relative to the user's upper torso in order to situate the targeted knee above the user's heart to alleviate knee swelling; and, which the user may use when he or she is at a rehabilitation phase that is centered primarily on passive range of motion and management of swelling, as well as when the user progresses to a stage in the rehabilitation process where he or she may focus more directly on developing strength and functional independence.
There are patented inventions which may be of some use for rehabilitating a knee that has been injured or which has undergone surgery. For example, U.S. Pat. No. 5,074,549 to Harvey discloses a frame structure with a horizontal bar which enables the leg to be flexed such that the leg is approximately vertical. Thereafter, weights or other pressure devices may be used to navigate the lower leg so as to exercise the knee joint. However, Harvey requires the user to grip the device and apply a pulling force on the invention itself, in order for the user to situate his or her upper thigh in certain positions. Also, Harvey does not appear designed for truly passive exercising of the user's knee through extension or flexion.
Another invention known to the inventor is the knee rehabilitation device of Mason et al., U.S. Pat. No. 5,509,894. Mason, et al. involves suspension of the user's leg using a bar, located above the leg, to which straps are attached. The user's leg is strapped just above the knee, and also around the ankle. However, Mason et al. does not place the user's leg in a truly perpendicular position, relative to the surface on which it is placed, and thus is relatively limited in the ranges through which the user may move his or her leg.
An exercise device detailed in expired U.S. Pat. No. 3,717,144 to Bimler describes a device wherein both the upper leg and lower leg are supported by sections which pivot to allow the knee to bend. The upper and lower leg remain supported during movement. The Bimler device appears to allow no more than approximately 90 degrees of bend in the knee during flexion, which may diminish the invention's utility for users who are have progressed to a point in the rehabilitation process of being able to tolerate a fuller range of knee bend.
Another exercise device is U.S. Pat. No. 4,844,454 to Rogers. This device features a hinged platform to which the upper leg and lower leg are strapped. The hinge action of the platform is facilitated by manual manipulation of a handle attached to the platform. The Rogers device appears to work the user's leg from and between an approximately extended leg position, to a leg position where the knee is flexed to approximately 90 degrees. Thus, Rogers provides a relatively limited range of motion during exercise.
A knee exercise device by Brooks is described in U.S. Pat. No. 4,784,121. The user of this device sits on a plate which is placed in a chair. The plate is attached to pivotally mounted levers and linkage whereby the user may manually control resistance when lowering or extending the leg. The knee can be flexed so that the leg is approximately straight. However, like Rogers and Bimler, the range of motion for bending the knee is limited to approximately 90 degrees. Also, the knee is positioned below the user's heart, and thus may have limited utility for the controlling of swelling that may be present in the user's knee.
Therefore, while there are currently inventions which appear to be of use for knee rehabilitation while offering such advantages as being portable, comfortable, safe to use, and easily adaptable for users of all body types, there does not appear to be any one device that offers these advantages while allowing the user to exercise the knee in a position which helps to reduce swelling, while also offering substantial versatility with the degree of range-of-motion and resistance exercising that the user may undertake in accordance with the strength, pain, and tissue-healing constraints with which the user may be coping at various phases of the rehabilitation process.